DOCSLIB.ORG

The Gemmological Laboratory Book a Guide for the Management and Technical Operations of Gemmological Laboratories

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Gemmological Laboratory Book a Guide for the Management and Technical Operations of Gemmological Laboratories © CIBJO 2020 All rights reserved GEMMOLOGICAL COMMISSION 2020 - 1 2020–1 2020-12–22 CIBJO/Laboratories CIBJO/GEMMOLOGICAL COMMISSION The Gemmological Laboratory Book A Guide for the Management and Technical Operations of Gemmological Laboratories i © CIBJO 2020 All rights reserved GEMMOLOGICAL COMMISSION 2020 — 1 Table of Contents FOREWORD ............................................................................................................................................. III INTRODUCTION ........................................................................................................................................ V 1. SCOPE ............................................................................................................................................. 6 2. NORMATIVE REFERENCES ............................................................................................................... 6 3. TERMS AND DEFINITIONS ............................................................................................................... 7 3.1. AUDIT ...............................................................................................................................7 3.2. CALIBRATION .....................................................................................................................7 3.3. CERTIFICATE .....................................................................................................................7 3.4. CERTIFIED REFERENCE MATERIALS — CRMS .....................................................................7 3.5. COMPETENT SUBCONTRACTOR ...........................................................................................7 3.6. GEM MATERIALS ................................................................................................................7 3.7. GEMMOLOGICAL LABORATORY ............................................................................................8 3.8. GEMMOLOGY .....................................................................................................................8 3.9. GEMOLOGICAL LABORATORY ..............................................................................................8 3.10. GEMOLOGY .......................................................................................................................8 3.11. GRADING ..........................................................................................................................8 3.12. INTERNAL AUDIT.................................................................................................................8 3.13. INTERNAL CALIBRATIONS ....................................................................................................8 3.14. LABORATORY / LAB ............................................................................................................8 3.15. QUALITY AND TECHNICAL RECORD ......................................................................................8 3.16. REFERENCE STANDARDS AND REFERENCE MATERIALS .........................................................8 3.17. REPORT ............................................................................................................................9 3.18. SAMPLING .........................................................................................................................9 3.19. SI UNITS – INTERNATIONAL SYSTEM OF UNITS .....................................................................9 3.20. SUBCONTRACT ..................................................................................................................9 3.21. TEST .................................................................................................................................9 3.22. TRACEABILITY....................................................................................................................9 3.23. REPRODUCIBILITY OF RESULTS ...........................................................................................9 4. MANAGEMENT REQUIREMENTS ..................................................................................................... 9 4.1. ORGANISATION ..................................................................................................................9 4.2. MANAGEMENT SYSTEMS.................................................................................................. 10 4.3. DOCUMENT CONTROL ..................................................................................................... 10 4.4. REVIEW OF CUSTOMER REQUESTS ................................................................................... 11 4.5. SUBCONTRACTING OF TESTS ........................................................................................... 11 4.7. COMPLAINTS .................................................................................................................. 11 4.8. CORRECTIVE ACTION ...................................................................................................... 12 4.9. ADDITIONAL AUDITS ........................................................................................................ 12 4.10. CONTROL OF RECORDS ................................................................................................... 12 4.11. INTERNAL AUDITS ............................................................................................................ 12 4.12. MANAGEMENT REVIEWS .................................................................................................. 12 5. TECHNICAL REQUIREMENTS .......................................................................................................... 13 5.1. PERSONNEL ................................................................................................................... 13 5.2. ACCOMMODATION AND ENVIRONMENTAL CONDITIONS ....................................................... 13 5.3. EQUIPMENT .................................................................................................................... 14 5.4. TESTING AND GRADING ................................................................................................... 14 5.5. REFERENCE STANDARDS AND REFERENCE MATERIALS ...................................................... 14 5.6. SAMPLING ...................................................................................................................... 15 5.7. ASSURING THE QUALITY OF TEST AND GRADING RESULTS .................................................. 15 5.8. REPORTING THE RESULTS ............................................................................................... 15 5.9. AMENDMENTS TO TEST REPORTS ..................................................................................... 16 6. TEST METHOD PROTOCOL ............................................................................................................. 16 6.1. TEST METHODS GEMSTONES ........................................................................................... 16 6.2. TEST METHODS PEARLS AND ORGANIC GEM MATERIALS .................................................... 54 6.3. TEST METHODS DEFINITIONS ........................................................................................... 63 6.4. TEST METHODS REFERENCES .......................................................................................... 67 INDEX ................................................................................................................................................... 208 ii © CIBJO 2020 All rights reserved GEMMOLOGICAL COMMISSION 2020 — 1 Foreword CIBJO is the French acronym for the Confédération Internationale de la Bijouterie, Joaillerie, Orfèvrerie, des Diamants, Perles et Pierres, which translates as the International Confederation of Jewellery, Silverware, Diamonds, Pearls and Stones (normally shortened to the International Jewellery Confederation). Founded in 1926 as BIBOAH, a European organisation whose mission was to represent and advance the interests of the jewellery trade in Europe, it was reorganised in 1961 and renamed CIBJO, in 2009 it was once again reorganised and officially named “CIBJO, The World Jewellery Confederation”. Today CIBJO, which is domiciled in Switzerland, is a non-profit confederation of national and international trade associations including commercial organisations involved in the jewellery supply chain. It now has members from countries representing all five continents of the world. CIBJO printed its first deliberations on terminology and trade practices in 1968. It is the task of CIBJO to record the accepted trade practices and nomenclature for the industry throughout the world. The records of the trade practices complement existing fair trade legislation of a nation or in the absence of relevant national laws they can be considered as trading standards. In countries where laws or norms exist, which conflict with the laws, norms or trade practices in other countries, CIBJO will support the national trade organisations to prevent trade barriers developing. The purpose of CIBJO is to encourage harmonisation, promote international co-operation within the jewellery industry, consider issues which are of concern to the trade worldwide and to communicate proactively with members. Foremost amongst these the aim is to protect consumer confidence in the industry. CIBJO pursues all of these objectives through informed deliberation and by reaching decisions in accordance with its Statutes.
Load more

Recommended publications
  • Summer 2006 Gems & Gemology Gem News
    EDITOR Brendan M. Laurs ([email protected]) CONTRIBUTING EDITORS Emmanuel Fritsch, IMN, University of Nantes, France ([email protected]) Henry A. Hänni, SSEF, Basel, Switzerland ([email protected]) Franck Notari, GIA GemTechLab, Geneva, Switzerland ([email protected]) Kenneth V. G. Scarratt, GIA Research, Bangkok, Thailand ([email protected]) COLORED STONES AND tusk fragments. The amber in figure 1 was eventually ORGANIC MATERIALS acquired by Barry Schenck of M. M. Schenck Jeweler Inc., Chattanooga, Tennessee, who recently loaned it to GIA for Alaskan amber. Few may think of Alaska as a source of examination. Mr. Schenck has counted more than 30 amber, but the Inuit people have long collected this organ- insects trapped inside the piece, as well as other organic ic gem from northern beach gravels between Harrison Bay materials, including an apparent seedpod. GIA subsequent- and Smith Bay on the Arctic Ocean. In Gemstones of ly purchased the piece (Collection no. 35840). North America (D. Van Nostrand Co., Princeton, NJ, Most of the insects were eye-visible, though others 1959), J. Sinkankas noted that locals refer to the amber as were best seen with magnification (up to 40×). Prominent auma, which translates as “live coal.” were a mosquito, spiders, beetles, gnats, ants, and possibly In 1943, an American soldier stationed in Alaska found a bee (see, e.g., figure 2). Other inclusions consisted of gas a 117.8 g chunk of amber (figure 1) while strolling along bubbles and debris that was probably associated with the the coast. Subsequent visits to the area yielded other trees from which the amber formed.
    [Show full text]
  • Crystal Chemistry of the Monazite and Xenotime Structures Yuxxnnc Nr
    American Mineralogist, Volume 80, pages2I-26, 1995 Crystal chemistry of the monazite and xenotime structures YuxxnNc Nr, JonN M. Hucnns Department of Geology, Miami University, Oxford, Ohio 45056' U.S.A. ANrrrotvv N. M.q'nr,lNo 48 PageBrook Road, Carlisle, Massachusetts01741' U.S.A. Arsrnlcr Monazite and xenotime, the RE(PO,) dimorphs, are the most ubiquitous rare earth (RE) minerals, yet accuratestructure studiesof the natural phaseshave not been reported. Here we report the results of high-precision structure studies of both the natural phasesand the synthetic RE(PO4)phases for all individual stable rare earth elements. Monazite is monoclinic, P2r/n, and xenotime is isostructural with zircon (spacegroup 14r/amd)- Both atomic arrangementsare basedon [001] chains of intervening phosphate tetrahedra and RE polyhedra, with a REO, polyhedron in xenotime that accommodates the heavy lanthanides(Tb-Lu in the synthetic phases)and a REO, polyhedron in monazite that preferentially incorporatesthe larger light rare earth elements(Ia-Gd). As the struc- ture "transforms" from xenotime to monazite, the crystallographic properties are com- parable along the [001] chains, with structural adjustments to the different sizes of RE atoms occurring principally in (001). There are distinct similarities betweenthe structuresthat are evident when their atomic arrangementsare projected down [001]. In that projection, the chains exist i! (100) planes, with two planes per unit cell. In monazite the planes are offset by 2.2 A along [010], relative to those in xenotime, in order to accommodate the larger light RE atoms. The shift of the planes in monazite allows the RE atom in that phaseto bond to an additional 02' atom to complete the REO' polyhedron.
    [Show full text]
  • Phenomenal Gemstones Possess Striking Optical Effects, Making Them Truly a Sight for Sore Eyes
    THE PHENOMENAL PROPERTIES OF GEMS Phenomenal gemstones possess striking optical effects, making them truly a sight for sore eyes. Here is GIA’s guide to understanding what makes each phenomenon so uniquely brilliant. ASTERISM CROSSING BANDS OF REFLECTED LIGHT CREATE A SIX-RAYED STAR-LIKE APPEARANCE. ASTERISM OCCURS IN THE DOME OF A CABOCHON, AND CAN BE SEEN IN GEMS LIKE RUBIES AND SAPPHIRES. ADULARESCENCE THE SAME SCATTERING OF LIGHT THAT MAKES THE SKY BLUE CREATES A MILKY, BLUISH-WHITE GLOW, LIKE MOONLIGHT SHINING THROUGH A VEIL OF CLOUDS. MOONSTONE IS THE ONLY GEM THAT DISPLAYS IT. AVENTURESCENCE FOUND IN NATURAL GEMS LIKE SUNSTONE FELDSPAR AND AVENTURINE QUARTZ, IT DISPLAYS A GLITTERY EFFECT CAUSED BY LIGHT REFLECTING FROM SMALL, FLAT INCLUSIONS. CHATOYANCY OTHERWISE KNOWN AS THE “CAT’S EYE” EFFECT, BANDS OF LIGHT ARE CAUSED BY THE REFLECTION OF LIGHT FROM MANY PARALLEL, NEEDLE-LIKE INCLUSIONS INSIDE A CABOCHON. NOTABLE GEMS THAT DISPLAY CHATOYANCY INCLUDE CAT’S EYE TOURMALINE AND CAT’S EYE CHRYSOBERYL. IRIDESCENCE ALSO SEEN IN SOAP BUBBLES AND OIL SLICKS, IT’S A RAINBOW EFFECT THAT IS CREATED WHEN LIGHT IS BROKEN UP INTO DIFFERENT COLORS. LOOK FOR IT IN FIRE AGATE AND OPAL AMMONITE (KNOWN BY THE TRADE AS AMMOLITE). LABR ADORESCENCE A BROAD FLASH OF COLOR THAT APPEARS IN LABRADORITE FELDSPAR, IT’S CAUSED BY LIGHT INTERACTING WITH THIN LAYERS IN THE STONE, AND DISAPPEARS WHEN THE GEM IS MOVED. INSIDER’S TIP: THE MOST COMMON PHENOMENAL COLOR IN LABRADORITE IS BLUE. PLAY OF COLOR THE FLASHING RAINBOW-LIKE COLORS IN OPAL THAT FLASH AT YOU AS YOU TURN THE STONE OR MOVE AROUND IT.
    [Show full text]
  • The Secondary Phosphate Minerals from Conselheiro Pena Pegmatite District (Minas Gerais, Brazil): Substitutions of Triphylite and Montebrasite Scholz, R.; Chaves, M
    The secondary phosphate minerals from Conselheiro Pena Pegmatite District (Minas Gerais, Brazil): substitutions of triphylite and montebrasite Scholz, R.; Chaves, M. L. S. C.; Belotti, F. M.; Filho, M. Cândido; Filho, L. Autor(es): A. D. Menezes; Silveira, C. Publicado por: Imprensa da Universidade de Coimbra URL persistente: URI:http://hdl.handle.net/10316.2/31441 DOI: DOI:http://dx.doi.org/10.14195/978-989-26-0534-0_27 Accessed : 2-Oct-2021 20:21:49 A navegação consulta e descarregamento dos títulos inseridos nas Bibliotecas Digitais UC Digitalis, UC Pombalina e UC Impactum, pressupõem a aceitação plena e sem reservas dos Termos e Condições de Uso destas Bibliotecas Digitais, disponíveis em https://digitalis.uc.pt/pt-pt/termos. Conforme exposto nos referidos Termos e Condições de Uso, o descarregamento de títulos de acesso restrito requer uma licença válida de autorização devendo o utilizador aceder ao(s) documento(s) a partir de um endereço de IP da instituição detentora da supramencionada licença. Ao utilizador é apenas permitido o descarregamento para uso pessoal, pelo que o emprego do(s) título(s) descarregado(s) para outro fim, designadamente comercial, carece de autorização do respetivo autor ou editor da obra. Na medida em que todas as obras da UC Digitalis se encontram protegidas pelo Código do Direito de Autor e Direitos Conexos e demais legislação aplicável, toda a cópia, parcial ou total, deste documento, nos casos em que é legalmente admitida, deverá conter ou fazer-se acompanhar por este aviso. pombalina.uc.pt digitalis.uc.pt 9 789892 605111 Série Documentos A presente obra reúne um conjunto de contribuições apresentadas no I Congresso Imprensa da Universidade de Coimbra Internacional de Geociências na CPLP, que decorreu de 14 a 16 de maio de 2012 no Coimbra University Press Auditório da Reitoria da Universidade de Coimbra.
    [Show full text]
  • Crystal Morphology and Xrd Peculiarities of Brazilianite from Different Localities
    NAT. CROAT. VOL. 20 No 1 1¿18 ZAGREB June 30, 2011 original scientific paper / izvorni znanstveni rad CRYSTAL MORPHOLOGY AND XRD PECULIARITIES OF BRAZILIANITE FROM DIFFERENT LOCALITIES ANDREA ^OBI]*1,VLADIMIR ZEBEC2,RICARDO SCHOLZ3, VLADIMIR BERMANEC1 &SANDRA DE BRITO BARRETO4 ¹Faculty of Science, Institute of Mineralogy and Petrography, Horvatovac 95, Zagreb, Croatia 2Croatian Natural History Museum, Demetrova 1, Zagreb, Croatia 3Department of Geology, School of Mining, Federal University Ouro Preto, Ouro Preto, MG, Brazil 4Department of Geology, Federal University of Pernambuco, Av. Academico Hélio Ramos. S/N. 5 andar., Cidade Universitária, Recife, PE, Brasil ^obi}, A., Zebec, V., Scholz, R., Bermanec, V. & de Brito Barreto, S.: Crystal morphology and xrd peculiarities of brazilianite from different localities. Nat. Croat., Vol. 20, No. 1., 1–18, 2011, Zagreb. Forty four brazilianite crystals from several localities in Brazil, Rwanda and Canada were measured on a two-circle goniometer to determine brazilianite morphology. Twenty forms were recorded; six of them have not been recorded before. All faces in the [001] zone are striated along crystallographic axis c. All striated forms in the [001] zone exhibit multiple signals. Two of the signals observed on the form {110} are always very clear. There is an exception on one crystal where just one face, (110), exhibits only one clear signal. Five groups of habits were recorded, two of them new to this mineral species. Eleven samples were examined by X-ray diffraction for calculation of the unit cell parameters yield- ing a=11.201(1)–11.255(2) Å, b=10.1415(5)–10.155(1) Å, c=7.0885(7)–7.119(2) Å and b=97.431(7)–97.34(1) °.
    [Show full text]
  • Monazite, Rhabdophane, Xenotime & Churchite
    Monazite, rhabdophane, xenotime & churchite: Vibrational spectroscopy of gadolinium phosphate polymorphs Nicolas Clavier, Adel Mesbah, Stephanie Szenknect, N. Dacheux To cite this version: Nicolas Clavier, Adel Mesbah, Stephanie Szenknect, N. Dacheux. Monazite, rhabdophane, xenotime & churchite: Vibrational spectroscopy of gadolinium phosphate polymorphs. Spec- trochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Elsevier, 2018, 205, pp.85-94. 10.1016/j.saa.2018.07.016. hal-02045615 HAL Id: hal-02045615 https://hal.archives-ouvertes.fr/hal-02045615 Submitted on 26 Feb 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Monazite, rhabdophane, xenotime & churchite : vibrational spectroscopy of gadolinium phosphate polymorphs N. Clavier 1,*, A. Mesbah 1, S. Szenknect 1, N. Dacheux 1 1 ICSM, CEA, CNRS, ENSCM, Univ Montpellier, Site de Marcoule, BP 17171, 30207 Bagnols/Cèze cedex, France * Corresponding author: Dr. Nicolas CLAVIER ICSM, CEA, CNRS, ENSCM, Univ Montpellier Site de Marcoule BP 17171 30207 Bagnols sur Cèze France Phone : + 33 4 66 33 92 08 Fax : + 33 4 66 79 76 11 [email protected] - 1 - Abstract : Rare-earth phosphates with the general formula REEPO4·nH2O belong to four distinct structural types: monazite, rhabdophane, churchite, and xenotime.
    [Show full text]
  • Blue Sapphire Engagement Ring, RG-2817U Dramatic Color And
    Blue Sapphire Engagement Ring, RG-2817u Dramatic color and unusual elegance come together in this vintage style blue sapphire engagement ring. The 18k white gold band of this engagement ring is set along the shoulders and shank with a collection of seventy-four round brilliant cut diamonds that total 0.52 carats. Eight of these diamonds, four on each side, are arranged in a floral design. The diamond flowers flank a bewitching blue sapphire at the center. This is a vintage style (new) blue sapphire engagement ring. Options None Item # rg2817u Metal 18k white gold Weight in grams 4.6 Special characteristics A matching band is available and may be purchased separately. Please see item RG-2817wb. Condition New Diamond cut or shape round brilliant Diamond carat weight 0.52 Diamond mm measurements 1.4-0.9 Diamond color G-H Diamond clarity VS1 Diamond # of stones 74 Gemstone name Natural Corundum (sapphire) Gemstone cut or shape round faceted mixed cut Gemstone carat weight 1.05 Gemstone type Type II Gemstone clarity VS Gemstone hue very very slightly greenish blue Gemstone tone 4-Medium Light Gemstone saturation 4-Moderately Strong Gemstone # of stones 1 Top of ring length (N-S) 6.75 mm [0.26 in] Width of shank at shoulders 4.85 mm [0.19 in] Width of shank at base 2.25 mm [0.09 in] Ring height above finger 6.9 mm [0.27 in] Other ring info For new rings like this one, the gram weight, diamond and gemstone carat weights, color, and clarity, as well as other jewelry details, may vary from the specifications shown on this page, but are similar in quality.
    [Show full text]
  • The Journal of Gemmology Editor: Dr R.R
    he Journa TGemmolog Volume 25 No. 8 October 1997 The Gemmological Association and Gem Testing Laboratory of Great Britain Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street, London Eel N SSU Tel: 0171 404 1134 Fax: 0171 404 8843 e-mail: [email protected] Website: www.gagtl.ac.uklgagtl President: Professor R.A. Howie Vice-Presidents: LM. Bruton, Af'. ram, D.C. Kent, R.K. Mitchell Honorary Fellows: R.A. Howie, R.T. Liddicoat Inr, K. Nassau Honorary Life Members: D.). Callaghan, LA. lobbins, H. Tillander Council of Management: C.R. Cavey, T.]. Davidson, N.W. Decks, R.R. Harding, I. Thomson, V.P. Watson Members' Council: Aj. Allnutt, P. Dwyer-Hickey, R. fuller, l. Greatwood. B. jackson, J. Kessler, j. Monnickendam, L. Music, l.B. Nelson, P.G. Read, R. Shepherd, C.H. VVinter Branch Chairmen: Midlands - C.M. Green, North West - I. Knight, Scottish - B. jackson Examiners: A.j. Allnutt, M.Sc., Ph.D., leA, S.M. Anderson, B.Se. (Hons), I-CA, L. Bartlett, 13.Se, .'vI.phil., I-G/\' DCi\, E.M. Bruton, FGA, DC/\, c.~. Cavey, FGA, S. Coelho, B.Se, I-G,\' DGt\, Prof. A.T. Collins, B.Sc, Ph.D, A.G. Good, FGA, f1GA, Cj.E. Halt B.Sc. (Hons), FGr\, G.M. Howe, FG,'\, oo-, G.H. jones, B.Se, PhD., FCA, M. Newton, B.Se, D.PhiL, H.L. Plumb, B.Sc., ICA, DCA, R.D. Ross, B.5e, I-GA, DGA, P..A.. Sadler, 13.5c., IGA, DCA, E. Stern, I'GA, DC/\, Prof. I.
    [Show full text]
  • June 2008 'Tairus' Created Gems: “Part I - Beryl”
    Sponsored by Ministry of Commerce & Industry Volume 51 Lab Information Circular June 2008 'Tairus' Created Gems: “Part I - Beryl” In the Volume 49 of Lab Information Circular, November 2007, PleochroismPleochroism: : Dichroism varied from weak in aquamarine to we reported “Synthetic Beryl of Paraiba colour” produced by very strong in darker coloured varieties like purple pink or Tairus Co. Ltd. in order to take the advantage of the popularity of orange red (see figure 2). 'Paraiba' tourmalines. Thereafter, we procured sets of various coloured beryls and corundum from the same manufacturer for our research and reference purpose. The study of these sets has been divided into two parts; this issue describes the study of beryl set, while the study of corundum set will be published in the next issue. 2.a 2.c 2.e The Beryl set consisted of five colour varieties (figure 1), namely, green (emerald), light blue (aquamarine), electric greenish blue (paraiba type), purple pink and orange red. All specimens were facetted as square step and measured 6 X 6 mm. 2.b 2.d 2.f Figure 2 Pleochroic colours of Tairus created Beryls Absorption Spectrum:Spectrum : The spectrum varied as per the colour variety; emerald showed a typical chromium spectrum while 'paraiba' colour displayed a strong band at around 430 nm. Purple pink and orange red varieties exhibited strong bands at 460 to 490 and 550 to 600 nm. UV fluorescence:fluorescence : All samples were inert to long wave as well as short wave UV light. Figure 1 Chelsea Filter Reactioneaction: : Emerald revealed a red glow while all Standard gemmological tests and advanced analysis on FTIR other varieties were either inert or did not displayed any reaction.
    [Show full text]
  • Mineral Collecting Sites in North Carolina by W
    .'.' .., Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie RUTILE GUMMITE IN GARNET RUBY CORUNDUM GOLD TORBERNITE GARNET IN MICA ANATASE RUTILE AJTUNITE AND TORBERNITE THULITE AND PYRITE MONAZITE EMERALD CUPRITE SMOKY QUARTZ ZIRCON TORBERNITE ~/ UBRAR'l USE ONLV ,~O NOT REMOVE. fROM LIBRARY N. C. GEOLOGICAL SUHVEY Information Circular 24 Mineral Collecting Sites in North Carolina By W. F. Wilson and B. J. McKenzie Raleigh 1978 Second Printing 1980. Additional copies of this publication may be obtained from: North CarOlina Department of Natural Resources and Community Development Geological Survey Section P. O. Box 27687 ~ Raleigh. N. C. 27611 1823 --~- GEOLOGICAL SURVEY SECTION The Geological Survey Section shall, by law"...make such exami­ nation, survey, and mapping of the geology, mineralogy, and topo­ graphy of the state, including their industrial and economic utilization as it may consider necessary." In carrying out its duties under this law, the section promotes the wise conservation and use of mineral resources by industry, commerce, agriculture, and other governmental agencies for the general welfare of the citizens of North Carolina. The Section conducts a number of basic and applied research projects in environmental resource planning, mineral resource explora­ tion, mineral statistics, and systematic geologic mapping. Services constitute a major portion ofthe Sections's activities and include identi­ fying rock and mineral samples submitted by the citizens of the state and providing consulting services and specially prepared reports to other agencies that require geological information. The Geological Survey Section publishes results of research in a series of Bulletins, Economic Papers, Information Circulars, Educa­ tional Series, Geologic Maps, and Special Publications.
    [Show full text]
  • Refinement of the Crystal Structure of Ushkovite from Nevados De Palermo, República Argentina
    929 The Canadian Mineralogist Vol. 40, pp. 929-937 (2002) REFINEMENT OF THE CRYSTAL STRUCTURE OF USHKOVITE FROM NEVADOS DE PALERMO, REPÚBLICA ARGENTINA MIGUEL A. GALLISKI§ AND FRANK C. HAWTHORNE¶ Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada ABSTRACT The crystal structure of ushkovite, triclinic, a 5.3468(4), b 10.592(1), c 7.2251(7) Å, ␣ 108.278(7), ␤ 111.739(7), ␥ 71.626(7)°, V 351.55(6) Å3, Z = 2, space group P¯1, has been refined to an R index of 2.3% for 1781 observed reflections measured with MoK␣ X-radiation. The crystal used to collect the X-ray-diffraction data was subsequently analyzed with an electron microprobe, 2+ 3+ to give the formula (Mg0.97 Mn 0.01) (H2O)4 [(Fe 1.99 Al0.03) (PO4) (OH) (H2O)2]2 (H2O)2, with the (OH) and (H2O) groups assigned from bond-valence analysis of the refined structure. Ushkovite is isostructural with laueite. Chains of corner-sharing 3+ 3+ {Fe O2 (OH)2 (H2O)2} octahedra extend along the c axis and are decorated by (PO4) tetrahedra to form [Fe 2 O4 (PO4)2 (OH)2 3+ (H2O)2] chains. These chains link via sharing between octahedron and tetrahedron corners to form slabs of composition [Fe 2 (PO4)2 (OH)2 (H2O)2] that are linked by {Mg O2 (H2O)4} octahedra. Keywords: ushkovite, crystal-structure refinement, electron-microprobe analysis. SOMMAIRE Nous avons affiné la structure cristaline de l’ushkovite, triclinique, a 5.3468(4), b 10.592(1), c 7.2251(7) Å, ␣ 108.278(7), ␤ 111.739(7), ␥ 71.626(7)°, V 351.55(6) Å3, Z = 2, groupe spatial P¯1, jusqu’à un résidu R de 2.3% en utilisant 1781 réflexions observées mesurées avec rayonnement MoK␣.
    [Show full text]
  • SYNTHETIC GEM MATERIALS in the 2000S GEMS & GEMOLOGY WINTER 2010 Figure 1
    SYNTHETIC GEM MATERIALS INTHE2000S: A DECADE IN REVIEW Nathan Renfro, John I. Koivula, Wuyi Wang, and Gary Roskin The first decade of the 2000s brought a constant flow of previously known synthetics into the marketplace, but little in the way of new technology. The biggest development was the commer- cial introduction of faceted single-crystal gem-quality CVD synthetic diamonds. A few other inter- esting and noteworthy synthetics, such as Malossi hydrothermal synthetic emeralds and Mexifire synthetic opals, also entered the market. Identification of synthetic gem materials continued to be an important function of—and, in some cases, challenge for—gemologists worldwide. he development of synthetics and the method- lished literature that the most significant develop- ologies used to detect new and existing materi- ments—and the focus of most research—during this Tals is of great importance to the international decade involved the production of gem-quality syn- gem community. Indeed, whether a synthetic gem thetic diamonds, primarily those grown by the com- was grown in the 2000s or the 1880s, today’s gemol- paratively new CVD (chemical vapor deposition) ogists must still be prepared to deal with it. Many process. Who can forget the September 2003 cover of synthetic gems were prominent in the marketplace Wired magazine, with a diamond-pavéd “supermod- in the first decade of the 2000s (see, e.g., figure 1). el” next to the headlines “$5 a carat. Flawless. Made The decade also saw some new synthetics. Among in a lab.”? This article proclaimed that “The dia- the synthetic colored stones introduced was the mond wars have begun,” and touted the potential for Malossi hydrothermal synthetic emerald (Adamo et outright cheap but extremely high-quality colorless al., 2005), which was gemologically similar to both and fancy-colored synthetic diamonds grown by two Russian synthetic emeralds and those manufactured very different processes (CVD and HPHT).
    [Show full text]